This invention relates to the treatment of and the prevention of vaginal infections and the prevention of transmission of sexually transmitted diseases. The methods of this invention may be used to kill or inactivate virus, bacteria, chlamydia, rickettsia, mycoplasma and other potentially pathogenic microorganisms in humans and other mammals.
The following abbreviations used in the following disclosure are defined as follows:
______________________________________ Povidone Povidone USP and equivalent products. Povidone has a molecular weight of above about 30 kd, the average molecular weight being about 40 kd typically. Povidone is polyvinyl pyrrolidone of the type generally available from GAF and BASF. Povidone Povidone complexed with iodine. Povidone iodine iodine typically comprises about 5 weight percent of iodine, plus about 10 weight percent iodide. LMW Polyvinyl pyrrolidone that has an average molecular Povidone weight of about 15,000 kd, typically 15,000 to 25,000 kd. ______________________________________
Povidone-iodine is a widely used commercial product. Povidone-iodine, abbreviated here as povidone iodine is a complex of molecular iodine with polyvinyl pyrrolidone. Povidone iodine complexes of the type under consideration have been described in the literature and are marketed by The Purdue-Frederick Co. When percent concentrations are referred to in connection with povidone iodine, the percentage refers to the percent of povidone iodine by weight, based upon the weight of the solution or material to which the povidone iodine is added. Thus, a 1 weight percent (.sup.w /o) solution of povidone iodine indicates that enough povidone iodine has been dissolved to result in a concentration of 1 .sup.w /o povidone iodine. In most instances, povidone iodine is added as a solution, e.g. 10% solution in water, pH about 1.5, but it can be added as a powder or otherwise. Povidone iodine powder contains approximately 85% povidone, 10% I and 5% iodide. A 10% solution of this powder contains 1% free, available iodine. (Gershenfeld, Am. J. Surgery 94, 938 (1957)).
Many and diverse diseases are transmitted sexually. Among the more common sexually transmitted diseases are condylomata acuminata (venereal warts), gonorrhea, syphilis, herpes simplex, granuloma venereum, chancroid, granuloma inguinale, non-gonococcal urethritis, acute pelvic inflammatory disease, vaginitis, and anorectal disease, and, of increasing concern, AIDS. Commonly sexually transmitted disease-causing organisms include Neisseria gonorrhoeae, Chlamydia trachomatis, Papillomavirus, Ureaplasma urealyticum, Mycoplasma hominis, Trichomonas vaginalis and Candida species.
Condylomata acuminata (venereal warts) is a sexually transmitted disease which has increased markedly in both adults and children during the past 15 years. The human papilloma virus is notoriously difficult to treat and often requires multiple office visits utilizing a variety of treatment modalities. Venereal warts are an ancient disease, but the relationship between certain human papillomavirus serotypes and genital neoplasia is just being recognized. Women are at higher risk for development of neoplasia from the infection and are more likely to be reinfected, because a male partner's lesions may be invisible without application of acetic acid or examination of a urethral smear. Other factors that favor progression to cancer are young age at first exposure, multiplicity of exposures, and immunosuppression.
Nonoxynol-9, a detergent that is widely used as a spermicide, has limited antibiotic activity; however, it does not kill or inactivate papillomavirus, the causative organism for venereal warts.
Vaginitis is a wide-spread disease which may be transmitted sexually or through other means. Vaginitis is a manifestation of a local infection by T. vaginalis, Candida, or Gardnerella vaginalis or other organisms. This invention has application to the treatment of vaginal diseases whether sexually transmitted or acquired through other contacts.
Herpesviruses, of which CMV is a member, represent a very large group of viruses which are responsible for, or involved in, cold sores, shingles, a venereal disease, mononucleosis, eye infections, birth defects and probably several cancers. Three subfamilies are of particular importance. The alpha subfamily includes HSV 1 (herpes simplex virus 1 ) which causes cold sores, fever blisters, eye and brain infections, HSV 2 (herpes simplex virus 2) which cause genital ulceration, and HSV 3 (HSV varicella zoster) which causes chicken pox, shingles and brain infections. The beta subfamily includes HSV 5, the principal member of which is CMV discussed above. The gamma subfamily includes HSV 4 (Epstein-Barr) which cause infectious mononucleosis and is involved in Burkitt's lymphoma and nasopharyngeal carcinoma.
The use of elemental iodine as an antiseptic dates back to about 1839. It is used today for various medicinal purposes. The combination of iodine with various solubilizing polymers led to a class of new compositions known as iodophors, which dominate the market once satisfied by simple alcoholic or aqueous iodine solutions. The iodine complexes with either nonionic surfactants, eg, polyethylene glycol mono(nonylphenyl)ether, or poly(vinylpyrrolidone) (povidone). The complexes function by rapidly liberating free iodine in water solutions. They exhibit good activity against bacteria, molds, yeasts, protozoa, and many viruses; indeed, of all antiseptic preparations suitable for direct use on humans and animals and upon tissues, only povidone iodine is capable of killing all classes of pathogens: gram-positive and gram-negative bacteria, mycobacteria, fungi, yeasts, viruses and protozoa. Most bacteria are killed within 15 to 30 seconds of contact. These iodophors are generally nontoxic, nonirritating to the skin and nonirritating upon short term application to membranes, non-sensitizing, and noncorrosive to most metals (except silver and iron alloys). Medicinal povidone iodine preparations include aerosol sprays, gauze pads, lubricating gels, creams, solutions, douche preparations, suppositories, gargles, perineal wash solutions, shampoos, and skin cleansers and scrubs. Povidone iodine preparation are applied topically to the skin and to membranes, e.g. vaginal membranes, and in infected wounds and surgical incisions. The uses continue to be largely medicinal, though some iodophors are used in industrial sanitation and disinfection in hospitals, building maintenance, and food-processing operations. There has been some interest in the use of iodine for purification of potable water and swimming pools. Two other iodine-containing compounds, p-tolyl diiodomethyl sulfone and p-chlorophenyldiiodomethyl sulfone have been recommended as preservatives.
Iodine and iodine-containing compounds and preparations are employed extensively in medicine, eg, as antiseptics, as drugs administered in different combinations in the prophylaxis and treatment of certain diseases, and as therapeutic agents in various thyroid dyscrasias and other abnormalities. Iodine is a highly reactive substance combining with proteins partly by chemical reaction and partly by adsorption. Therefore its antimicrobial action is subject to substantial impairment in the presence of organic matter such as serum, blood, urine, milk, etc. However, where there is no such interference, non-selective microbicidal action is intense and rapid. A saturated aqueous solution of iodine exhibits anti-bacterial properties. However, owing to the low solubility of iodine in water (33 mg/100 ml at 25.degree. C.), reaction with bacteria or with extraneous organic matter rapidly depletes the solution of its active content. Iodide ion is often added to increase solubility of iodine in water. This increase takes place by the formation of triiodide, I.sub.2 +I.sup.- =I.sub.3.sup.-. An aqueous solution of iodine and iodide at a pH of less than 8 contains mainly free diatomic iodine I.sub.2 and the triiodide I.sub.3.sup.- The ratio of I and I.sup.- depends upon the concentration of iodide.
An important solubilizing agent and carrier for iodine is polyvinyl pyrrolidone (povidone), one grade of which is identified as povidone USP. Povidone iodine, is widely used externally on humans as an antiseptic. Such products are marketed as Betadine and Isodine, povidone iodine products and the preparation of such products are described in U.S. Pat. Nos. 2,707,701, 2,826,532, and 2,900,305 to Hosmer and Siggia, assigned to GAF Corporation and in a number of GAF Corporation publications; see, e.g. Tableting with Povidone USP (1981 ) and Povidone Polyvinylpyrrolidone (1982). Povidone iodine powder contains approximately 85% povidone, 10% I and 5% Iodide. A 10% solution of this powder contains 1% free, available iodine. (Gershenfeld, Am. J. Surgery 94, 938 (1957)).
Under ordinary conditions, povidone is stable as a solid and in solution. The single most attractive property of povidone is its binding capability. This property has permitted utilization in numerous commercial applications. Small quantities of povidone stabilize aqueous emulsions and suspensions, apparently by its absorption as a thin layer on the surface of individual colloidal particles. The single most widely studied and best characterized povidone complex is that of povidone-iodine. For example, hydrogen triiodide forms a complex with povidone that is so stable that there is no appreciable vapor pressure. It is superior to tincture of iodine as a germicide.
The use of conventional povidone iodine, i.e. compositions which have an povidone to iodine ratio of under 10 to 1, typically 8.5 to 1, in vaginal treatments has been reported. Women being prepared for total abdominal hysterectomy were treated by insertion of povidone-iodine tampons that remained in the vagina until the end of the operation. Statistically significant decreases both in infectious morbidity and in the percentage of positive cultures from the cervix and vagina, at the time of the operation resulted from this use of povidone-iodine. Vaginal Preparation with Povidone-Iodine before Abdominal Hysterectomy, Zakut Z; Lotan M; Bracha Y, Clin Exp Obstet Gynecol 14 (1). 1987. 1-5. The use of povidone-iodine (`Betadine`) pessaries in the treatment of candidal and trichomonal vaginitis was reported by Henderson JN; Tait IB Curr Med Res Opin 1975, 3 (3) p157-62. In the Henderson et al study one hundred and thirty-five women suffering from trichomonal, candidal, or both infections simultaneously, were treated with povidone-iodine pessaries, 2 pessaries being inserted nightly. Ninety-nine women were given a 7-day course of treatment, but the results obtained were disappointing, and the authors do not recommend such a regime for routine treatment. Better results were obtained with the recommended 14-day course. A further 36 women suffering from chronic trichomonal and/or candidal infections which had previously resisted orthodox treatment were given a prolonged 28-day course of pessary treatment. The results obtained were very encouraging, 92% of the trichomonal and 96% of the candidal infections being cured. Furthermore, although povidone-iodine is slightly less effective in trichomoniasis, most patients suffering from a chronic infection (candidal, as well as trichomonal) were cured by the one preparation. Side-effects did occur. Subjective symptoms, especially any offensive odor, disappeared within 3 days of the start of the treatment. The authors recommend that the 28-day course of povidone-iodine pessaries is used in those cases where trichomoniasis or candidiasis has been a therapeutic problem in the past, particularly if the patient is currently on the oral contraceptive pill.
Other uses of povidone iodine in vaginal preparations and as a spermicidal preparations have been reported. The treatment of minor vaginal irritation with disposable povidone iodine preparation (Betadine Medicated Douche) in cases associated with infertility was reported by Beaton J H., et al, Int J Fertil 29 (2). 1984. 109-112. The effect of chemical intravaginal contraceptives and betadine on ureaplasma urealyticum was studied by Amortegui, A. J.; Melder, R. J.; Meyer, M. P.; Singh, B., CONTRACEPTION; 30(2), pp. 135-142 1984. The purpose of the study was to find a barrier contraceptive agent capable of controlling infections and sexual transmission of Ureaplasma urealyticum from the female genital tract, especially to help reduce non-gonococcal urethritis in males caused by this organism. In vitro antimicrobial activity of Betadine(TM-Purdue Frederick Co.) against the eight serotypes of the organism was investigated. The results indicate that some of these contraceptives produce partial inhibition of the Ureaplasma at low dilutions, while Betadine produces a ureaplasmicidal effect up to dilutions of 1:64. Quantitative studies of the interaction of polyvinylpyrrolidone iodine and spermatozoa were conducted by Pfannschmidt N; Nissen HP, Z Hautkr Nov. 15, 1988. In this study, 27 ejaculates were incubated together with polyvinyl pyrrolidone iodine diluted with physiological saline solution in various proportions. 10 minutes, 1 hour, 4 hours, and 20 hours later, we determined the percentages of mobile and viable spermatozoa in both the native and the incubated seminal fluid. 1% polyvinyl pyrrolidone iodine solution was totally spermicidal already after 10 minutes of incubation. 0.1% solution only slightly reduced the sperm motility and viability. 0.01% polyvinyl pyrrolidone iodine solution even resulted in a temporary increase of motility.
Douche preparations containing povidone iodine are widely used, and efforts have been made to treat and/or prevent vaginal infections with povidone iodine.
Notwithstanding considerable interest in povidone iodine-based spermicide-microbicides, no satisfactory product has been developed and frequent regular use of povidone iodine products frequently results in irritation of the vaginal membrane and considerable discomfort to the user. It also is evident that no effective physical form of povidone iodine for use as a spermicide-biocide has been available. The invention described hereinafter solves the problems, both recognized and unrecognized, that have plagued workers in this field.